1011020021 has 8 divisors (see below), whose sum is σ = 1105845600. Its totient is φ = 916680240.

The previous prime is 1011020009. The next prime is 1011020027. The reversal of 1011020021 is 1200201101.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1011020021 is a prime.

It is a super-2 number, since 2×1011020021² = 2044322965725680882, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1011019990 and 1011020008.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011020027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117086 + ... + 125423.

It is an arithmetic number, because the mean of its divisors is an integer number (138230700).

Almost surely, 2^1011020021 is an apocalyptic number.

1011020021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1011020021 is a deficient number, since it is larger than the sum of its proper divisors (94825579).

1011020021 is a wasteful number, since it uses less digits than its factorization.

1011020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242899.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1011020021 is about 31796.5410225704. The cubic root of 1011020021 is about 1003.6599289120.

Adding to 1011020021 its reverse (1200201101), we get a palindrome (2211221122).

The spelling of 1011020021 in words is "one billion, eleven million, twenty thousand, twenty-one".